City's sycamore trees hit by fungus, effects visible

The springtime rains and cool temperatures have long passed, but their effects remain evident on American sycamores trees across Norwalk.

The trees are missing leaves and look skeletonized, according to experts.

This year, the large trees were hit particularly hard by sycamore anthracnose, a fungus infection which flourishes under wet conditions and causes the trees to lose or never sprout leaves.

"This is not an uncommon thing. It just happened to be amplified by the (weather) conditions. We had a really wet-and-humid May. In some cases, we saw 100-percent defoliation. Anyone that had a sycamore in Norwalk was affected," said Bob Bociek, branch manager with Almstead Tree & Shrub Care Co. of Stamford, which has a tree-planting contract with the city of Norwalk. "Right now, most of the trees seem to have made a recovery. But the energy used to refoliate may weaken the tree in the long time."

According to the U.S. Forest Service, the sycamore has the largest diameter trunk of any North American hardwood, and mature trees are typically free of branches to a height of about 70 feet.

The largest tree in Connecticut is the Pinchot Sycamore that grows along the Farmington River in Simsbury. At high noon, its canopy would shade half a football field. It's also the largest sycamore in New England and is believed to be the second largest in the U.S.

The tree is in Simsbury's Pinchot Sycamore Park, where Route 185 crosses the Farmington River. A picnic table is nearby.

Rich Whitehead, a licensed arborist and board member of the Norwalk Tree Advisory Council, estimates that hundreds of sycamore trees in Norwalk were affected by the disease. The effects of disease are visible, among other places, on sycamore trees off Riverside Avenue near the Norwalk River.

With the wet spring weather passed and summer now in full swing, the trees are recovering from the disease but remain weakened. At this point, Bociek advises sycamore owners to water their trees in July and August by letting a garden hose trickle near the base of the tree for several hours, once every seven to 10 days.

In addition, sycamore owners should lightly fertilize their trees in late August or early September. For long-term protection against sycamore anthracnose, tree owners may have a licensed arborist apply an injection.

"There is a product that can be injected into the tree and that will help control the issue for two-and-a-half to three years," Bociek said. "There are systemic injections available that offer multi-season control."

On July 1, Almstead Tree & Shrub began a new three-year contract with the city of Norwalk, as part of the city's tree-planting program. Under the old three-year contract, which expired in June, residents requested 212 trees and shrubs. Of those, four requests were for sycamore trees. As such, the city did not include sycamores in its new contract with the company, according to Paul Sotnik, assistant civil engineer in the city's Department of Public Works and deputy tree warden.

"Sycamores are not on (the new) list but it has nothing to do with the disease," Sotnik said.

Jeffrey Ward, head of the forestry department of the Connecticut Agricultural Experiment Station, said most sycamores in Connecticut are suffering from a fungus infection -- sycamore anthracnose -- that's causing the trees to appear as if they're missing most of their leaves.

"The sycamores are feeling the effects of anthracnose -- it's really bad this year," said Ward, who is also the experiment station's chief scientist. "If the tree is healthy, it'll get through it, but if it isn't, it might not."

Ward blamed the infection on a spring that was more humid than normal. He added that there is little that can be done at this point, other than to take a wait-and-see approach. "The time to treat is in the early spring, before it leafs out," he said.

But, he added, the tree can usually endure a severe anthracnose infection.

"It's a tough hardwood species," he said. "It's one of the fastest-growing hardwoods -- it can reach up to 250 feet tall with a trunk 20 feet in diameter -- that's getting up into California redwood territory."

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